1. Field of the Invention
This invention relates to a valve which isolates a patient from a provider of care when such provider of care attempts to resuscitate such patient by forcing the provider's breath into the patient's lungs.
2. Description of the Related Art
A variety of United States and foreign patents have been issued for devices which provide some degree of isolation between a patient and a care provider who is attempting to resuscitate the patient.
These include the following U.S. Pat. Nos. 3,158,152; 3,242,921; 3,923,054; 4,520,811; 4,811,730; 4,998,530; 5,005,568; 5,020,529; 5,146,914; 5,295,478; and 5,357,951. Similar foreign patents are the following: German (DDR) patent no. 53 856, German (FDR) patent no. 2 203 850, and French patent no. 2 664 167.
But none of these prior patents provides filters for all pathways that may be taken by breath exhaled by the care provider and the patient while having a path that would enable the often weak incipient breath of a patient to escape from the patient's lungs to the atmosphere even if the care provider is exhaling at the same time. Moreover, none of these prior patents provides an air-tight seal while allowing rotation between the portion of the valve to which a mouthpiece may be attached for the care provider and the portion of the valve to which a mask or a mouthpiece may be attached for the patient--a movement essential for maximizing comfort for both patient and care provider during often lengthy attempts at resuscitation. Increased comfort for the care provider will usually translate into both a longer period during which resuscitation may be attempted and greater alertness of the care provider during this period. Finally, none of the prior patents provides two filter segments in the most direct pathway between the patient and the care provider to minimize the possibility of fluid passing between the care provider and the patient while also establishing a space between such filter segments which is large enough to accommodate any fluid that manages to evade one of the filter segments without significantly obstructing the flow of breath from the care provider.